1. Field of the Invention
The present invention relates to an electron beam exposure apparatus, an electron beam exposure method, a semi conductor device manufacturing method, a mask, and a mask manufacturing method. More particularly, the present invention relates to the electron beam exposure apparatus for exposing a pattern on a wafer accurately.
2. Description of Related Art
As for an electron beam exposure apparatuses using batch exposure such as a block exposure apparatus and a cell exposure apparatus, or a mask pattern projection electron beam exposure apparatus called EPL, a desired pattern is exposed by shaping the electron beam by a transmissive pattern of a mask, reducing cross-section of the electron beam, and projecting it on the mask. In such a system, it is premised that reduction ratio from the mask to the wafer is decided by arrangement and power of a lens of an optical system and does not depend on the shape of the pattern.
However, when the beam current is increased especially for increasing throughput, there is a problem that a reduction ratio changes. Moreover, also in the electron beam exposure apparatus using a variable rectangle, when rectangle size of the electron beam is enlarged, there is a problem of a discrepancy between a shot size irradiated actually on the wafer and a desired shot size.